Fix errors on ValidatingAdmissionPolicyBindings for the CEL for Admission Control blog & doc (#38893)

* Fix errors on ValidatingAdmissionPolicyBindings for the CEL for Admission Control blog

* Fix namespaceSelector error

* Fix namespaceSelector errors

Author: mathieu-benoit

content/en/blog/_posts/2022-12-20-validating-admission-policies-alpha/index.md

@@ -60,12 +60,14 @@ kind: ValidatingAdmissionPolicyBinding
 metadata:
   name: "demo-binding-test.example.com"
 spec:
-  policy: "demo-policy.example.com"
+  policyName: "demo-policy.example.com"
   matchResources:
     namespaceSelector:
-    - key: environment,
-      operator: In,
-      values: ["test"]
+      matchExpressions:
+      - key: environment
+        operator: In
+        values:
+        - test
 ```
 
 This `ValidatingAdmissionPolicyBinding` resource binds the above policy only to
@@ -115,14 +117,16 @@ kind: ValidatingAdmissionPolicyBinding
 metadata:
   name: "demo-binding-production.example.com"
 spec:
-  policy: "demo-policy.example.com"
-  paramsRef:
+  policyName: "demo-policy.example.com"
+  paramRef:
     name: "demo-params-production.example.com"
   matchResources:
     namespaceSelector:
-    - key: environment,
-      operator: In,
-      values: ["production"]
+      matchExpressions:
+      - key: environment
+        operator: In
+        values:
+        - production
 ```
 
 ```yaml

content/en/docs/reference/access-authn-authz/validating-admission-policy.md

@@ -193,9 +193,10 @@ spec:
   matchResources:
     namespaceSelector:
       matchExpressions:
-      - key: environment,
-        operator: NotIn,
-        values: ["test"]
+      - key: environment
+        operator: NotIn
+        values:
+        - test
 ```
 
 And have a parameter resource like:
@@ -222,7 +223,7 @@ spec:
   matchResources:
     namespaceSelector:
       matchExpressions:
-      - key: environment,
+      - key: environment
         operator: Exists
 ```